Evaluation of intratympanic dexamethasone for treatment of refractory sudden sensorineural hearing loss

To observe and compare the efficacy of intratympanic application of dexamethasone (DXM) for the treatment of refractory sudden sensorineural hearing loss (SSNHL), the DXM was given in three different ways: by tympanic membrane injection, by drip through a ventilation tube, and by perfusion through a round window catheter. We conducted a nonrandomized retrospective clinical trial involving 55 patients with refractory SSNHL. For 21 patients (the perfusion group), DXM (2.5 mg/0.5 ml) was perfused transtympanically through a round window catheter using an infusion pump for 1 h twice a day for 7 d giving a total amount of 35.0 mg. For 23 patients (the injection group), DXM (2.5 mg/time) was injected by tympanic membrane puncture at intervals of 2 d on a total of four occasions giving a total amount of 10.0 mg. For 11 patients (the drip group), DXM (2.5 mg/0.5 ml) was dripped via a ventilation tube placed by myringotomy, once on the first day and twice a day for the remaining 6 d giving a total amount of 32.5 mg. Thirty-two patients with refractory SSNHL who refused to undertake further treatments were defined as the control group. Hearing recovery and complications were compared among the groups. Hearing results were evaluated based on a four-frequency (0.5, 1.0, 2.0, 4.0 kHz) pure tone average (PTA). Post-treatment audiograms were obtained one month after treatments were completed. The improvements in average PTA for the perfusion, injection, and drip groups were 9.0, 8.6, and 1.7 dB, respectively. Hearing improvement was significantly greater in the perfusion and injection groups than in the control group (1.4 dB) (P < 0.05). In the perfusion group, 8 out of 21 patients (38.1%) had a PTA improvement of 15-56 dB (mean 29.8 dB); in the injection group, 8 out of 23 patients (34.8%) had a PTA improvement of 16-54 dB (mean 24.9 dB); in the drip group, 1 of 11 patients (9.1%) had a PTA improvement of 26.0 dB; in the control group, 3 out of 32 patients (9.4%) had a PTA improvement of 15-36 dB (mean 14.9 dB). Topical intratympanic application of DXM is a safe and effective method for the treatment of SSNHL cases that are refractory to conventional therapies.